1. Field of the Invention
The present invention relates in general to tool chucks for attachment of accessories to power drivers, and more particularly to a tool chuck having chuck jaws that may be actuated via power from the driver's transmission.
2. Description of Related Art
Conventional tool chucks may have a turn ring that is rotatable using a chuck key to extend and retract chuck jaws. Although such tool chucks are generally thought to provide acceptable performance, they are not without shortcomings. For example, the conventional tool chuck requires cumbersome chuck key operations, chuck key retention, and other inconveniences.
In view of the shortcomings associated with chuck keys, tool chucks have been developed that have a turn ring (or sleeve) that is rotated manually, without using a chuck key, to tighten the chuck jaws. Other developments include a tool chuck that utilizes power from the power driver to open and close the chuck jaws. To this end, the tool chuck may be provided with a sleeve that is axially moveable to a position in which the sleeve is grounded (i.e., rotationally fixed) to the housing of the power driver. Thus, when the driver is powered up, a spindle of the driver (and consequently the chuck jaws) rotates relative to the sleeve. The relative rotation between the spindle and the sleeve may tighten or loosen the chuck jaws.
Conventional keyless tool chucks have associated disadvantages. For example, they require an operator to manipulate the sleeve (i.e., rotate the sleeve and/or slide the sleeve axially). Such manipulations may be difficult, especially when the operator attempts to simultaneously insert an accessory into the chuck jaws. Also, an operator may inadvertently release a grounded condition between the sleeve and the tool housing when the tool is powered up.